Method of molding building blocks



F. J. STRAUB METHOD OF MOLDING BUILDING BLOCKS May 29, 1928.

Filed Nov .n 16, 1925 R OM T V f, m

WITNESSVES Patented May 29, 1928.

'UNITED sTATEsPA-TENT OFFICE.

FRANCIS J. STRAUB, 0F NEW KENSINGTON, PENNSYLVANIA.

METHOD. 0F HOLDING BUILDING BLOCKS.

Application filed November 16, 1926. Serial No. 148,676.

y valuable where the material or aggregate used is sufficiently lightand porous to admit of the application directly upon it of plaster orstucco,or the application of wooden trim etc., by nailing,- as may bedone in the well known cinder block construction.

The 'block of -the present invention is ca` pable ofv manufacture on amachine equipped with a double row ofl tamps, one row tamping thematerial or aggregate in the mold at the front of the cores, the othertamps working. at the back thereof. The tamps are also preferably variedin weight to eifect variation in the tamped density, and when desiredthe density of the Wall portion formed by the heavier tampsmayfbeifurther improved by the use of a vibrating plate or wall likethat shown in my co-pending application, Serial No. 148,674 filed Nov.ie, 1926.y

Referring to the drawings illustrating one preferred method of carryingout myinvention- Fig.` 1 shows in plan view a characteristic form ofbuilding block. indicating the relative density at front and backrespectively;

Fig. 2 is a vertical sectional view showing' the mold of a moldingmachine and itstamps adapted to produce said block;

' Fig. 3 is a view similar to Fig. 1,-showire a Irlllfidifiedconstruction with a thinner front Wa 4 is a view similar-to Fig. 2,showing the mold and its tamps for producing such block; l v i Fig. 5 isa perspective view of the building block of Fig. 1.

Referring to the drawings, 2 is the usual mold ofa standard block pressmounted upon The other side, being .lessthe supporting plate 3, havingthe cores L for formation of the usual coro openings a of the block, asshown in Fig. l.

The material for the block A is filled into the molding space in theusual Way, a pallet 5 having been first inserted for removal of thefinished block, and the block'is tamped` within the Walls and around thecores by a plurality of tamps 6 and 7 of Well known construction.

For the purpose offeifectino` the densifying action, tamps 7 .arematerially heavier than tamps 6, so that, as they fall in the tampingoperation, they will crowd the material at that side of the mold closertogether, during the time the lighter tamps 6 are doing the same Work atthe other side.

In order to bring thefinal tampedbody portion of the block up to a finalcommon level the yaggregate is supplied in a proportionately increasedamount at the denser side before or during-the tamping operation. Suchoperation continues until the mold is completely filled and'tamped up tothe desired level, after which any surplus material is removed byshifting iti-laterally across the top of the mold in the usual way.

For the purpose of imparting a smooth finished surface to the denserface of the block, one of the side walls of the mold 2 may bein theformof a longitudinally vi-` y brating plate 8.

Such vibration or alternatin movement of the plate will tend to trowesuch face, giving it a' substantially smooth finished surface, in themanner more fully described in thefsaid' co-pending application.

Thevblock may be of any desired dimensions,and the roportions of thewalls may be made to 4suit the conditions of use, or other variationsmay be adopted, within the scope' of the invention, as hereinafterclaimed.

Having described 4my invention, what I claim'. is: u v I 1. The processof making a concrete block ofa dense consistency at one side consistingin applying relatively heavy and light tamping'to opposite sides of theentire block while the mold.

2. The process of making a concreteblock of a dense consistency at oneside consisting in simultaneously Ifilling and tamping oon-` creteaggregate of normally uniform consistency ina mold with a relativelygreater amount of condensation at one side..

' 3. r1`he process of making a concrete "block 5 of a dense consistencyat one side consisting in simultaneously lling and tam'ping concreteaggregate of normally uniform consistency in a mold with a relativelygreater i amount of condensation and a relatively thinner Wall at oneside.k I

In testimony whereof I hereunto allix my signature.

FRANCIS J. STRAUB.

